I spent some time in the park with Tai Chi students and masters. The power comes from their legs, or their center of gravity rather than their hands. The hands are simply a delivery mechanism or tool to pass the energy. It is a subtle, yet counter-intuitive technique of transferring energy rather than using resistance. What they practice is a form of Tai Chi where they have to push or pull each other off balance. There is no striking but they are able to demonstrate proficiency at deflecting an opponents force to cause a loss of balance to the opponent or absorbing your energy and immediately sending your own force back to you causing you to lose balance, wind up in a lock, or confronting the floor. One of the guys said learning Tai Chi helped improve his boxing and Thai kick boxing abilities and that the principles of Tai Chi helped him compete more effectively, rather than expending energy looking for ways to overpower a competitor. UFC competitors rely on a sprawl technique to avoid being taken to the mat, but the leaning stance leaves them vulnerable to falling face down, although I have not seen this happen in a match because the other competitor is meeting the resistance with resistance rather than using that moment as an advantage to using the other opponents motion against himself. For example, a master in this form of Tai Chi will step toward the force when his head/neck is being pulled forward/down throwing his opponent off balance, to the floor, etc. The traditional UFC approach is to attempt to pull your neck/head back to avoid an upcoming knee to the head. The match and the rematch when Rich Franklin fought Anderson Silva, Franklin lost momentum and succumbed to knees to the head from Silva. The lack of a technique to deflect or absorb and send back the downward pressure of the clinch with Mr. Silva resulted in Mr. Franklin losing the matches. When a competitor fails to maintain his balance he cannot effectively defend himself so a study of Tai Chi would be of value to UFC competitors, the only way to prove how valuable it would be is to give it a try.